The “Simultan” process is a distinctively different and secure offset printing process created by the Applicant more than five decades ago, which process is widely applied in the security printing industry. This process is increasingly being challenged by the ever-increasing quality of readily available counterfeit methods of desktop publishing and commercial printing.
The Simultan process is radically different form commercial offset printing. Commercial offset printing presses create multicolour images using a number of separate printing units through which the paper runs in succession. The paper is travelling from one unit to the next to collect all separate colours one after the other on the substrate. However, the substrate is a flexible, living material that warps with pressure, humidity and temperature. Even with the best material these variations vary at random. Consequently colour to colour registration at the end of the printing process is slightly different for different areas of the print. Colour images printed on commercial offset printing presses are typically generated by combinations of microscopic dot arrays, which are sufficiently forgiving for these variations. In contrast, security prints produced on security offset printing presses, especially by way of the above-mentioned Simultan process, require a perfect plate to plate registration on the entire sheet. Here, the specific design of the Simultan offset printing press (as sold by the Applicant under the registered trade name Super Simultan®) comes into play. Indeed, rather than being based on the use of separate printing units as in the above-described commercial printing presses, the Simultan offset printing press (an example of which is illustrated in FIGS. 1A, 1B and 2 hereof) is based on a different principle, namely the collecting of the different colour images from the printing plates on a common blanket cylinder. In the Simultan press, such principle is actually applied simultaneously on both sides of the printing material, i.e. two blanket cylinders (one for each side) collect the colour patterns of the corresponding plate cylinders carrying the printing plates on the recto side and verso side respectively. With this principle, the precision of the registration between colours is no longer dependent on the fluctuations of substrates but only from the high precision mechanics of the press (gears, frames, bearings, cylinders, etc.) and the reproduction and mounting of the printing plates.
It is not enough to have a precise press, but all elements in the process must be equally precise. While the Simultan process exhibits technically unmatched printing performance, there is still a need to improve this process and achieve even higher printing accuracy and colour registration. In order to keep its leading edge in security printing and to maintain a safe distance from the existing and ever-evolving threats, the whole process, from the origination through plate-making and make-ready in the press, has been reviewed and upgraded with a view to provide unprecedented precision in an easy-to-master way and open the door to an entirely new class of security features to the security printing industry.